The present invention relates to a tourbillon mechanism adapted to improve the precision of operation of the regulating member and more particularly to improve the mechanical construction of such a mechanism, leading to higher precision of positioning of the pieces forming these mechanisms.
Tourbillon mechanisms have been known from the first device of this type designed by A. -L. Breguet in 1801 in a variety of embodiments.
Such a mechanism comprises a cage mounted pivotally in the case of the timepiece in question, this cage carrying all the escapement members and the regulator member. Due to the complexity and to the above-mentioned object of such a mechanism, all the elements of a tourbillon mechanism must be among other things positioned as precisely as possible.
Despite a large number of different embodiments of these mechanisms, the association and/or arrangement of several pieces in the conventional tourbillon mechanisms is still not optimal.
This relates first of all to the cage, which is comprised normally of an upper portion and a lower portion which were until now secured to each other by means of screw threaded posts. This conventional solution gives rise to problems as to the concentricity of all the elements of the cage relative to the access of the balance wheel and also as to the rigidity and weight of the cage as well as its assembly.
Moreover, the anchor and the escapement wheel are subject to conceivable improvements relating among other things to their positioning relative to each other with the help of the cage, even on an element fixed to this latter, so as to increase the precision of this positioning and the guidance of the elements during operation of the mechanism.
The object of the present invention is to overcome the mentioned drawbacks and to permit the production of a simple tourbillon mechanism with a reduced number of pieces and reduced weight, ensuring at the same time the concentricity of the elements and the rigidity of the cage as well as guaranteeing the easy and precise positioning of the anchor and the escapement wheel on the cage, simultaneously ensuring better guidance of this latter.
The object of the present invention is accordingly a tourbillon mechanism which is distinguished by the characteristics set forth in claims 1 and 6 and/or in the dependent claims.